Electrical condenser



March 17, 1931. R. H. AHLERS ELECTRICAL CONDENSER Filed March 27, 1924 ivy Patented Mar. 17, 1931 UNITED STATES PATENT OFFICE ROBERT H. AI-ILERS, F DAYTON, OHIO, ASSIGNOR TO THE DAYTON ENGINEERING LABORATORIES COMPANY, OF DAYTON, OHIO, A CORPORATION OF DELAWARE ELECTRICAL CONDENSER Application filed March 27, 1924. Serial No. 702,461..

This invention relates to condensers for electrical apparatus, and particularly for ignition apparatus for internal combustion engines.

One of the objects of the invention is to provide a condenser which is simple and compact and can be manufactured at relatively low cost.

Further objects and advantages of the present invention will be apparent from the following description reference being had to the accompanying drawing, wherein a preferred embodiment of one form of the present invention is clearly shown.

In the drawings:

Fig. 1 is a side view of a form of condenser including the present invention.

Fig. 2 is a sectional view of an assembled condenser on a larger scale than Fig. 1.

Fig. 3 is similar to Fig. 2, showing the parts before assembled.

Figs. 4 and 5 are plan views of certain parts shown in section in Fig. 3.

Referring to the drawings, the condenser 25 proper comprises two strips of metallic foil such as tin or aluminum foil and 21 which are separated by strips of non-conducting material 22. These strips are wound simultaneously upon a metallic core 23, the strip 20 30 being in contact with the core. The side mar- O the material and iron out the wrinkles.

After the condenser material has been wound to the desired diameter upon core 23 and covered by a non-conducting wrapping 19,.the condenser is impregnated in the ,usual manner with wax which tends to close up pores in the insulating strips 22 and also improve their dielectric strength. The condenser is now ready to be assembled in a metallic capsule-like container comprising two parts 24 and 25 which are adapted to be tele scopically engaged, member 25 being flared at 25a to receive the member 24. These members are made by a drawing process, and since the container is made in two parts instead of being a single tubular member with a closed end for receiving the condenser, the drawing process has been simplified.

The condenser is assembled first by assembling together the condenser core 23, metallic washers 26 and 27, non-conducting Washers 28 and 29, and the metallic container member 24. The condenser core is provided With a tubular extension 30 which extends through aligned apertures in the washers and in the end of container 24. By spinning over the end of the portion 30, the members 26, 28, 24, 29, and 27 are permanently fastened between the deformed end 31 of core 23 and the shoulder portion 32. The washer 27 is provided with points 33 struck out from the surface thereof, and the assembling of the core 23 and container 24, as shown in Fig. 2, causes the spirally disposed side margin of the foil strip 20 to be crushed together and to be engaged by the points 33 so as to provide an electrical connection between foil strip 20 and the core 30. The core 30 is provided with a tapped hole 34 for receiving a screw by means of which an electrical conductor may be at tached to the condenser.

A metallic washer 35 provided with points 36 is soldered to conductor 37 of thin sheet material. provided with a square opening 38 for receiving a square shoulder 39 of a screw 40, said shoulder being adapted to extend through the opening 38 and through a square opening 41 in a washer 42. The parts 25, 40, 42 are assembled together; washer 35 with the strip 37 attached. thereto is pressed against the margin of the foil 21 so that the spirally disposed margin is crushed together and the points 36 project into this margin; a washer 43 having resilient fingers 44 is placed adjacent the head of the screw while assembled within the container 25; and the container 25 is moved into the position shown in Fig. 2 so that the container members 24 The end of the container 25 is and 25 are telescopically engaged. Then the joint between these members is soldered at lUG 45. The strip 37 assists in providing a good electrical connection between the foil 21 and the member 25 The spring washer 43 tends to hold the washer in contact with the foil 2l and also holds the screw in position without requiring the screw to be soldered to the container 25. The screw 40 provides for attaching a terminal to the condenser for conveniently mounting the condenser vention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A condenser comprising, in combination, a metallic core, condenser material including insulated foil strips wound upon said core, one of said foil strips being electrically connected therewith, a metallic container including telescopically engaging members each embracing a substantial portion of the material, means for. insulatingly attaching the core and'material to one of the container members, and means for electrically connectlng the other foil strip with the container.

2. A condenser comprising, in combinatlon, a metallic core, condenser material including foil strips alternating with insulating strips all wound upon said core, the spirally wound foil margins being exposed, re-

spectively, adjacent opposite ends of the core, a metallic container including telescopically engaging members each embracing a substantial portion of the material, means for insulatingly attaching the core and material to one of the container members, means for electrically connecting one ofthe foils to the core including a washer engaging the core and the spirally wound margin of said foil, and means for electrically connecting the other foil strip with the container including a disc engaging the other exposed foil margin.

3. A condenser comprising in combination, a metallic core having condenser mate rial wound thereon, said material including foi strips with insulating material therebetween, the edges of alternate foil strips ex-' tending beyond theedges of the insulating material at the respective ends of the condenser," a metallic member adapted to fit over and electrically engage the core and also electrically engage the extending edge of the one foil strip; an insulating member on the said metallic member, a cup-shaped container adapted to fit over the core and condenser material insulatingly to support same; an insulating washer fitting over the end of the core extending from the container, said end being adapted to be spun over said washer whereby the condenser material and core are insulatingly and rigidly secured to the said container; a metallic member engaging thejedges of the foilextendingfrom the other end of the condenser material, a springengaging said metallic member, and a cover adapted to embrace the metallic member, spring and condenser material and fit telescopically on the first mentioned container, said cover being electrically connected to the foil strips engaged by the enclosed metallic member when it is placed in p0sition about thecontainer.

4. An electrical condenser comprising, in combination, a metal core, insulated foils wound directly upon the core, one of said foils being in direct contact with the core, a tubular metal case member having an apertured end wall through which'the core projects and to which the core is insulatingly connected, and a metal member electrically connected with another of the foils and cooperating with the tubular case member to provide an enclosure for the foils and core.

5. A condenser comprising, in combination, a metallic core; condenser material including foil strips alternating with insulating strips all wound upon said core, the spirally wound foil margins being'exposed, respectively, adjacent opposite ends of the core; a tubular case member for surrounding the condenser and having an apertured end wall through which the core projects to provide one of the condenser terminals; means.

for insulatingly attaching the core to said case member; a metal washer surrounding the core and electrically connected therewith, said washer engaging the spirally wound side margin of the foil adjacent thereto; and means for electrically connecting the foil margin at the other end of the condenser ma terial with the case member.

6. A condenser comprising, in combination, a metallic core; condenser material including foil strips alternating with insulating strips all wound upon said core, the spirally wound foil margins being exposed, re-

spectively, adjacent opposite ends of the core;

a tubular case memberfor surrounding the condenser and having an apertured end wall through'which the core projects to provide one of the condenser terminals; means for insulatingly attaching the core to said case member; a metal member in contact with the metal core and having a plurality of points for engaging the spirally wound side margin of the foil adjacent thereto in order to con nect one of said foils with the core; and means for electrically connecting the foil margin at the other end of the condenser material with the case member.

7. A condenser comprising, in combination, a metallic core; condenser material including foil strips alternating with insulating strips all wound upon said core, the spirally wound foil margins being exposed, re spectively, adjacent opposite ends of the core; a tubular case member for surrounding the condenser and having an apertured end wall throughwhich the core projects to provide one of the condenser terminals; means for insulatingly attaching the core to said case member; means for electrically connecting the foil margin adjacent the apertured end of the tubular case member with the core; and means for electrically connecting the foil margin at the opposite end of the condenser material with the condenser case member.

8. A condenser comprising, in combination, a metallic core; condenser material including foil strips alternating with insulating strips all wound upon said core, the spirally wound foil margins being exposed, respectively, adjacent opposite ends of the core; a tubular case member for surrounding the condenser and having an apertured end wall through which the core projects to provide one of the condenser terminals; means for insulatingly attaching the core to said case member; means for electrically connecting the foil margin adjacent the apertured end of the tubular case member with the core; a metal disc in contact with the foil margin at the opposite end of the condenser material; and means for electrically connecting said disc with the condenser case member.

9. A condenser comprising, in combination, a metallic core; condenser material including foil strips alternating with insulating strips all wound upon said core, the spirally wound foil margins being exposed, respectively, adjacent opposite ends of the core; a tubular case member for surrounding the condenser and having an apertured end wall through which the core projects to provide one of the condenser terminals; means for insulatingly attaching the. core to said case member; means for electrically connecting the foil margin adjacent the apertured end of the tubular case member with the core; a metal disc' in contact with the foil margin at the opposite end of the condenser material; a metal cover member attached to said tubular case member to provide a complete enclosure for the condenser material; and a resilient metallic member located between said disc and said metal cover member to press said disc against the adjacent foil margin and for making an electrical connection between the disc and the metal cover.

10. A condenser comprising, in combination, condenser material including cylindrically Wound foil strips alternating with insulating strips; a tubular metal case enclosing the material; a metalterminal insulatingly attached to the case adjacent one end thereof; means connecting a spirally formed margin of one of the foils with the terminal; and'means for connecting the other foil with the case, one of said means including a resilient member maintaining said foil connections.

11. A condenser comprising, in combination, condenser material including cylindrically wound foil strips'alternating with insulating strips; a tubular metal case enclosing the material; a metal terminal insulatingly attached to the case adjacent one end thereof; means for connecting one of the foils with the terminal; a metal disc in contact with a foil margin at the end of the condenser material remote from the terminal; and resilient means for electrically connecting said disc with the condenser case.

12. A condenser comprising, in combination, condenser material including cylindrically wound foil strips alternating with insulating strips; a tubular metal case enclosing the material; a metal terminal insulatingly attached to the case adjacent one end thereof; means ,for connecting one of the foils with the terminal; a metal disc in contact with a foil margin at the end of the con denser material remote from the terminal; a metal cover member attached to said tubular case member to provide a completeenclosure for the condenser material; and a resilient metallic member located between said disc and said metal cover member to press said disc against the adjacent foil margin and for making an electrical connection between the disc and the metal cover,

13. In a condenser, the combination of ametallic core, a pair of conducting stripswound upon said core with interposed layers of insulation between them and with one strip connected with said core, one edge of said strip projecting beyond one end of the insulation and crushed together and into contact with the end surface of one end of said core and one edge of the other strip projecting beyond the opposite end of said insulation and crushed together, a'surrounding casing, and means connecting the turns of said last strip with said casing.

In testimony whereof I hereto aflix my signature. I

ROBERT H. AHLERS. 

